Clinical analysis of mitochondrial encephalomyopathy with lactic acidosis and stroke -like episodes in children / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the clinical,imaging,pathological and molecular biological features of mitochondrial encephalomyopathy with lactic acidosis and stroke -like episodes(MELAS)in children.Methods The clinical,imaging,pathological and molecular biological features of 1 2 children with MELAS diagnosed through muscle biopsy or gene sequencing in the Fifth Affiliated Hospital of Zhengzhou University from January 201 1 to December 201 5 were retrospectively analyzed.Results (1 )Clinical featuresthe main manifestations included headache and vomiting in 1 1 cases,epileptic seizures in 9 cases,short stature in 8 cases,hairy in 7 cases,intolerance fatigue in 7 cases,cogni-tive decline in 7 cases,visual disturbance in 6 cases,hearing disturbance in 6 cases,and 5 cases had positive family history.In addition,7 cases had the serum lactic acid level increase in a rest for 1 0 min after exercise.(2)Imaging fea-tures4 cases showed bilateral basal ganglia calcification symmetry in 8 patients who underwent head CT scan.The most frequently involved parts of the lesion were occipital in 1 0 cases,temporal in 9 cases and parietal lobe in 7 cases in stroke -like episodes.The lesions were lamellar necrosis.The abnormal areas by MRI showed low signal intensity on T1 weighted imaging,high signal intensity on T2 weighted imaging and fluid attenuated inversion recovery,high or equal signal intensity on diffusion weighted imaging,high or low signal intensity on apparent diffusion coefficient;the lactate peak significantly increased on magnetic resonance spectroscopy.The distribution was not in accordance with the control region of the cerebral vessels.Dynamic observation revealed that the lesions were reversible and migratory.(3)Myo-pathological featuresmuscle biopsy was performed in all children,and ragged -red fibers were found in 1 0 cases by im-proved Gomori staining,strongly succinate dehydrogenase -reactive were found in 9 cases,and the lipid droplets slight-ly increased in 8 cases by oil red O staining.Besides,the crystalline inclusion bodies in mitochondria were arranged in a parking lotpattern in 9 cases by electromicroscope.(4)Molecular biological characteristicsthe mitochondrial gene mutations were analyzed in peripheral blood of 9 children and their parents,including 8 cases with A3243G muta-tion and 1 case with G13513A mutation.Five mothers had the same A3243G mutation site in 8 cases.Conclusions Children with MELAS have complex and varied clinical manifestations and certain characteristic of neuroimaging.More-over,muscle pathology and gene sequencing have important diagnostic value.Fully understanding the clinical,muscle pathology,imaging and molecular biological characteristics of children with MELAS can be helpful to the early diagnosis and treatment,also reduce misdiagnosis.